1. Field of the Invention
This invention relates to a means for preventing certain materials from migrating from the propellant grain into the silicone rubber insulation layer of a rocket motor.
2. Description of the Prior Art
It has recently been discovered that silicone rubber is an excellent insulator for rockets and ramjets. A layer of silicone rubber interposed between a solid rocket propellant grain and a metallic rocket motor case does an excellent job of insulating the case from heat damage when the propellant is burned. However, when solid propellant is cast and cured into a metallic shell lined internally with silicone insulation, propellant curatives will migrate from the propellant into the silicone rubber layer. When this occurs, a poorly cured propellant near the silicone-to-propellant interface results.